Feather

An artificial being originally seen as a set of special earrings used by Yuuri (tha same pair worn by future Kaoru in the visions, although one gets destroyed and it changes the future slightly accordingly). Feather wishes to protect Yuuri, along with everyone else. She gives one of the special earrings meant for Kaoru to Minamoto, asking him to investigate it. After some research from Fujiko in the Impalahen Kingdom, where the earrings were created, Feather is revealed to surpass the strength of Level 7 espers. Later events causes her to leave Yuuri into the care of B.A.B.E.L., where she eventually possesses a special gel-like material with special quantities, and formed into a human woman's body, although due to the strain from saving Minamoto and exercising various different level 7 powers, including healing severe injuries and teleportation which she lacked before, she reformed into the shape of a bird, and put under Minamoto's care, as B.A.B.E.L. is unable to contain her. Later she confesses to Minamoto that she is originally from the future with her powers and memories implanted into her by Kaoru, Aoi and Shiho's future selves, who made use of the Triple Boost to send her to the past with the intention to prevent the war between espers and normals to occur. She knows that changing the future will lead to her being erased from the space-time continuum, as with the war averted, so will be the reasons for her creation, but is still determined to acomplish the mission she is given by Kaoru and the others, as along their memories, she also has the will to create a peaceful future for them. After joining Hyoubu in a failed attempt to take down Black Phantom for good, she teleports Hyoubu's body to an alternate dimension to prevent it from being used by Gilliam to further advance his research while storing his memories into her body, assuming a different form resembling him during his childhood days. (Source: Wikipedia.org)